In situtransformation of Pd into β-PdH is the origin of the high selectivity for CO in the electrochemical CO2reduction reaction using Pd as the electrocatalyst.

Ethylene (CH) is one of the most important raw materials for chemical industry. The tandem reactions of CO-assisted dehydrogenation of ethane (CH) to ethylene creates an opportunity to effectively use the underutilized ethane from shale gas while mitigating anthropogenic CO emissions. Here we identify the most likely active sites over CeO-supported NiFe catalysts by using combined in situ characterization with density-functional theory (DFT) calculations. The experimental and theoretical results reveal that the Ni-FeO interfacial sites can selectively break the C-H bonds and preserve the C-C bond of CH to produce ethylene, while the Ni-CeO interfacial sites efficiently cleave all of the C-H and C-C bonds to produce synthesis gas. Controlled synthesis of the two distinct active sites enables rational enhancement of the ethylene selectivity for the CO-assisted dehydrogenation of ethane.

The oxygen evolution reaction (OER) has broad applications in electrochemical devices, but it often requires expensive and scarce Ir-based catalysts in acid electrolyte. Presented here is a framework to reduce Ir loading by combining core–shell iridium/metal nitride morphologies using in situ experiments and density functional theory (DFT) calculations. Several group VIII transition metal (Fe, Co, and Ni) nitrides are studied as core materials, with Ir/Fe4N core–shell particles showing enhancement in both OER activity and stability. In situ X-ray absorption fine structure measurements are used to determine the structure and stability of the core–shell catalysts under OER conditions. DFT calculations are used to demonstrate adsorbate binding energies as descriptors of the observed activity trends.